Question

In an incross of individuals of a G2 family during a G3 mutant screen, evidence of a new mutant would be:

	A. One half of the crosses would have 100% mutants.
	B. All of the crosses would have one quarter mutants.
	C. One quarter of the crosses would have one quarter mutants.
	D. One quarter of the crosses would display 50% mutants.
	E. One half of the crosses would have one half mutants.
	F. All of the crosses would have one half heterozygotes.
	G. Half of the crosses would have one half heterozygotes.
	H. All of the crosses would display 100% mutants.

Answer 1

In an incross of individuals of a G2 family during a G3 mutant screen, means when the cross of G2 family (let Ff) is carried out, the resulting offsprings are FF, Ff, Ff and ff are formed. The ratio of these offsprings are 3:1. In these indivisuals half of the offsprings are heterozygotes. So the evidence of a new mutant would be all of the crosses would have one half heterozygotes.

Hence answer (F) All of the crosses would have one half heterozygotes is right.